U.S. patent number 10,541,594 [Application Number 15/324,692] was granted by the patent office on 2020-01-21 for electrical linear machine.
This patent grant is currently assigned to Robert Bosch GmbH. The grantee listed for this patent is Robert Bosch GmbH. Invention is credited to Anton Paweletz, Li Xiang.
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United States Patent |
10,541,594 |
Paweletz , et al. |
January 21, 2020 |
**Please see images for:
( Certificate of Correction ) ** |
Electrical linear machine
Abstract
An electrical linear machine includes a stator that is fixed to
a housing and an armature that is configured to be axially
displaced and supports a permanent magnet. The stator has a first
stator yolk and a second stator yoke with the stator yolks each
forming a stator pole. The stator poles are arranged in a manner
distributed radially and uniformly around the armature. The first
stator yoke is associated with at least one coil to which current
is applied so as to generate a first magnetic flux through the
first stator yoke and the permanent magnet. A magnetic north pole
of the permanent magnet is associated with a stator pole of the
second stator yoke and a magnetic south pole of the permanent
magnet is associated with the other stator pole of the second
stator yoke in order to generate a second magnetic flux through the
second stator yoke.
Inventors: |
Paweletz; Anton (Fellbach,
DE), Xiang; Li (Stuttgart, DE) |
Applicant: |
Name |
City |
State |
Country |
Type |
Robert Bosch GmbH |
Stuttgart |
N/A |
DE |
|
|
Assignee: |
Robert Bosch GmbH (Stuttgart,
DE)
|
Family
ID: |
53191685 |
Appl.
No.: |
15/324,692 |
Filed: |
May 22, 2015 |
PCT
Filed: |
May 22, 2015 |
PCT No.: |
PCT/EP2015/061403 |
371(c)(1),(2),(4) Date: |
January 07, 2017 |
PCT
Pub. No.: |
WO2016/008627 |
PCT
Pub. Date: |
January 21, 2016 |
Prior Publication Data
|
|
|
|
Document
Identifier |
Publication Date |
|
US 20170207690 A1 |
Jul 20, 2017 |
|
Foreign Application Priority Data
|
|
|
|
|
Jul 15, 2014 [DE] |
|
|
10 2014 213 713 |
|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H02K
11/20 (20160101); H02K 11/33 (20160101); H02K
33/02 (20130101); H02K 41/03 (20130101); H02K
33/16 (20130101) |
Current International
Class: |
H02K
41/03 (20060101); H02K 11/33 (20160101); H02K
11/20 (20160101) |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
|
|
|
|
|
|
|
100 55 078 |
|
Jun 2002 |
|
DE |
|
62-171455 |
|
Jul 1987 |
|
JP |
|
2002-112520 |
|
Apr 2002 |
|
JP |
|
2008-206356 |
|
Sep 2008 |
|
JP |
|
Other References
International Search Report corresponding to PCT Application No.
PCT/EP2015/061403, dated Oct. 23, 2015 (German and English language
document) (5 pages). cited by applicant.
|
Primary Examiner: Zhang; Jue
Assistant Examiner: Iliya; Bart
Attorney, Agent or Firm: Maginot, Moore & Beck LLP
Claims
The invention claimed is:
1. An electrical linear machine, comprising: an armature that is
axially displaceable relative to a housing, and that includes a
permanent magnet having a magnetic north pole and a magnetic south
pole; and a stator that is fixed to the housing, and that includes:
a first stator yoke that has a first pair of stator poles; and a
second stator yoke that has a second pair of stator poles, the
second stator yoke rotationally offset from the first stator yoke
such that the first and second pairs of stator poles are
distributed radially and uniformly around the armature, wherein:
only the first stator yoke includes at least one coil configured to
be energized; and energizing the at least one coil generates a
first magnetic flux through the first stator yoke and the permanent
magnet, and wherein the permanent magnet is fixed at an orientation
such that the magnetic north pole of the permanent magnet is facing
toward a first stator pole of the second pair of stator poles, and
such that the magnetic south pole of the permanent magnet is facing
toward a second stator pole of the second pair of stator poles, so
that the permanent magnet generates a second magnetic flux through
the second stator yoke.
2. The linear machine as claimed in claim 1, further comprising: at
least one resilient element that applies an axial biasing force to
the armature such that when the at least one coil is not energized,
the permanent magnet is in a position located outside a first
magnetically neutral resting position.
3. The linear machine as claimed in claim 1, wherein: the permanent
magnet generates a first magnetic force that biases the armature
toward a first magnetically neutral resting position; the first
magnetic flux generated through the first stator yoke via
energizing of the at least one coil generates a second magnetic
force that counteracts the first magnetic force and biases the
armature toward a second magnetically neutral resting position: and
the first and second magnetic resting positions are axially spaced
apart from each other.
4. The linear machine as claimed in claim 1, further comprising: at
least one steel lamellae package positioned on the permanent magnet
and configured to guide the first magnetic flux.
5. The linear machine as claimed in claim 4, wherein: a respective
steel lamellae package of the at least one steel lamellae package
is positioned on each of the magnetic north pole of the permanent
magnet and the magnetic south pole of the permanent magnet; and
steel lamellae of the respective lamellae package extend
perpendicular to the second magnetic flux.
6. The linear machine as claimed in claim 1, wherein: each of the
first and second stator yokes has an open ring shape; and free ends
of the open ring shape of each of the first and second stator yokes
form the first and second pairs of stator poles, respectively.
7. The linear machine as claimed in claim 1, further comprising: a
sensor device is configured to sense the second magnetic flux
passing through the second yoke.
8. The linear machine as claimed in claim 7, further comprising: a
control unit configured to energize the at least one coil with
reference to the sensed second magnetic flux.
9. The linear machine as claimed in claim 7, wherein the sensor
device has a stator coil.
10. The linear machine as claimed in claim 1, wherein: the
permanent magnet includes a steel lamellae package on an axial end
face that faces inwards toward the first stator yoke; and steel
lamellae of the steel lamellae package extend perpendicularly to
the second magnetic flux.
11. The linear machine as claimed in claim 1, wherein: the first
stator yoke includes a first coil configured to be energized, and a
second coil configured to be energized the first coil and the
second coil are separated from each other by a steel lamellae
package ring; the permanent magnet generates a first magnetic force
that biases the armature toward a first magnetically neutral
resting position; and the steel lamellae package ring is positioned
so as to be a region of the permanent magnet when the armature is
in the first magnetically neutral resting position.
Description
This application is a 35 U.S.C. .sctn. 371 National Stage
Application of PCT/EP2015/061403, filed on May 22, 2015, which
claims the benefit of priority to Serial No. DE 10 2014 213 713.6,
filed on Jul. 15, 2014 in Germany, the disclosures of which are
incorporated herein by reference in their entirety.
BACKGROUND
The disclosure relates to an electrical linear machine having a
stator that is fixed to the housing, and having an armature that
can be relocated in an axial manner and that supports a permanent
magnet.
Electrical linear machines are fundamentally known. By way of
example the unexamined German application DE 100 55 078 C1 thus
discloses an electrical linear machine that operates as an
electrical reluctance machine in accordance with a transverse flux
principle in which in other words a magnetic flux extends in a
transverse manner (transversal) with respect to the direction of
movement of an oscillating armature (oscillator). By virtue of
electrically exciting this linear machine, it is intended to
overcome disadvantages that arise with linear machines that
generate the magnetic flux by means of providing permanent magnets.
In particular, it is intended thereby to overcome the disadvantage
that the degree of efficiency of linear machines that are excited
by permanent magnet rapidly decreases at higher operating
temperatures owing to a reversible demagnetization or said linear
machines can be permanently damaged in the event of an irreversible
demagnetization.
Furthermore, the unexamined Japanese application JP 2008-206356 A
discloses a linear machine in which the multiple permanent magnets
and also two electrically excitable coils are provided to operate
the machine. It is necessary to fix the permanent magnets by means
of non-magnetic elements which means an additional outlay in
construction and material costs, in particular if high operating
temperatures are to be expected.
SUMMARY
The electrical linear machine in accordance with the disclosure has
the advantage that a simple construction is provided at low costs
(in particular by means of simple, standardized lamination of the
magnetic circuit with magnetic steel sheets) that in particular
permanently ensures an oscillating operation of the armature. In
particular, because merely one coil that can be energized is
necessary to operate the electrical machine in accordance with the
disclosure, the construction and also the control of the electrical
machine is simple and particularly precise in comparison to known
electrical machines.
The electrical machine in accordance with the disclosure is
characterized by virtue of the fact that the stator comprises a
first and a second stator yoke that form in each case two stator
poles, wherein the stator poles are arranged distributed radially
and uniformly around an armature, and wherein at least one coil
that can be energized so as to generate a first magnetic flux
through the first stator yoke and the permanent magnet is allocated
to the first stator yoke, and wherein a magnetic north pole of the
permanent magnet is allocated to a stator pole of the second stator
yoke and a magnetic south pole of the permanent magnet is allocated
to the other stator pole of the second stator yoke in order to
generate a second magnetic flux through the second stator yoke. The
stator comprises in other words two stator yokes that in each case
form two stator poles. The stator poles are arranged uniformly
spaced with respect to one another by means of their arrangement
distributed uniformly over the periphery of the armature.
Expediently, the stator poles of a stator yoke lie opposite one
another. The armature having the permanent magnet lies in the air
gap between the stator poles. The north pole is allocated to one
stator pole of a stator yoke and the south pole is allocated to the
other stator pole of a stator yoke. The coil that can be energized
is allocated to the other stator yoke. A first magnetic flux can be
generated through the first stator yoke and through the second
stator yoke in a magnetic manner. The electrical machine that is
constructed in this manner generates both a magnetic transversal
flux component as well as a magnetic longitudinal component that
act simultaneously in order to effect the relocation, in particular
an oscillation of the armature in the axial direction. One coil
suffices in order to operate the electrical machine that in this
respect also operates preferably at least in part as a linear
reluctance machine. In particular, the linear machine is embodied
as a linear reluctance machine or as a hybrid linear reluctance
machine.
In accordance with an advantageous further development of the
disclosure, it is provided that at least one resilient element is
allocated to the armature, said resilient element pre-stressing the
armature in such a manner that the permanent magnet is located
outside a magnetically neutral resting position. The term "neutral"
or "magnetically neutral resting position" is to be understood as
the position of the permanent magnet in which the permanent magnet
is located in relation to the stator if external influences are not
acting upon said magnet. The permanent magnet would move into a
magnetically neutral resting position in relation to the stator
poles if the coil is not energized and the resilient element is not
provided. The armature is located in the non-energized state in a
magnetically pre-stressed position by means of providing the
resilient element that pre-stresses the armature in such a manner
that the resilient element lies outside its resting position so
that it is possible to reliably actuate said armature in a desired
direction and in a short period of time.
Furthermore, it is preferably provided that the permanent magnet
comprises a first magnetically neutral resting position that is
determined by means of the permanent magnet and a second
magnetically neutral resting position that is determined by means
of the coil that is energized, wherein the first and the second
magnetically neutral resting position are spaced axially from one
another in the axial direction. The first neutral resting position
is in this respect the above described resting position of the
armature or the permanent magnet. The second neutral resting
position is then achieved if the coil is energized and as a
consequence an electrically excited magnetic flux is generated in
the stator by means of which the armature is moved into a second
position, namely the neutral energized position. In particular, the
term "second neutral resting position" is to be understood to mean
the position in which the coil is energized with the maximum
current.
Moreover, it is preferably provided that at least one steel
lamellae package is allocated to the permanent magnet in order to
guide a magnetic flux. It is possible to influence the magnetic
flux in relation to the permanent magnet by means of the steel
lamellae package, in particular by means of aligning the steel
lamellae.
In particular, the steel lamellae can be arranged and/or aligned in
such a manner on the permanent magnet that a magnetic flux prevents
or at least reduces in a specific direction and is preferably
admitted in another direction. In particular, it is possible for
the first magnetic flux that is excited by means of the coil to be
guided past the permanent magnet, in particular without thereby
impairing the second magnetic flux.
In accordance with a preferred further development of the
disclosure, it is provided that in each case a steel lamellae
package is arranged on the north pole of the permanent magnet and
on the south pole of the permanent magnet and the steel lamellae of
said steel lamellae package extend perpendicular with respect to
the second magnetic flux. The lamellae thereby simultaneously
extend parallel to the first magnetic flux. As a consequence, the
first magnetic flux that is generated by means of the energized
coil is guided past the permanent magnet by means of the steel
lamellae while the second magnetic flux that is generated by means
of the permanent magnet can follow the alignment or the natural
magnetic field of the permanent magnet.
Furthermore, it is preferably provided that the stator poles
comprise in each case a steel lamellae package whose steel lamellae
extend in the direction of the respective magnetic flux to the
permanent magnet. It is possible by means of providing the steel
lamellae on the stator poles to advantageously guide the respective
magnetic flux towards the air gap between the stator poles or
between the stator poles and the permanent magnet. It is
particularly preferred that the first and/or the second stator yoke
are embodied altogether as steel lamellae package.
In accordance with a preferred further development of the
disclosure, it is provided that the respective stator yoke is
embodied in each case as an open stator ring whose free ends form
one of the stator poles. By virtue of being embodied as an open
stator ring, the respective stator yoke comprises two free ends
that lie opposite one another and form the stator poles in this
case. As a consequence, an advantageous magnetic flux is ensured
both when excited using the permanent magnet as well as when
excited electrically. The respective stator ring can be embodied in
a circular, oval or square shape. The respective stator yoke
particularly preferably comprises a projection that protrudes
radially inwards (in other words facing in the direction of the
stator poles or the air gap) on the side that lies opposite the
slot or air gap in order to optimize the first magnetic flux that
acts in the longitudinal direction of the armature.
Furthermore, it is preferably provided that the permanent magnet
comprises a steel laminate package on an end face that faces
inwards in relation to the first stator yoke and the steel lamellae
of said steel lamellae package extend perpendicular to the second
magnetic flux. As a consequence, the first magnetic flux is guided
in particular in the direction of the projection of the
corresponding stator yoke, said projection protruding radially
inwards, as a result of which the magnetic resistance reduces and
the magnetic flux is increased.
Moreover, in accordance with a preferred embodiment of the
disclosure it is provided that a sensor device, in particular
having sensor coils, is allocated to the second stator yoke so as
to ascertain the second magnetic flux. While the coil that can be
energized is allocated to the first stator yoke, a sensor device is
allocated to the second stator yoke, said sensor device
ascertaining the magnetic flux that is generated through the second
stator yoke. The magnetic flux through the stator yoke changes in
dependence upon the position of the permanent magnet in relation to
the stator pole of the second stator yoke so that in dependence
upon the ascertained magnetic flux it is possible to specify or
determine the position of the permanent magnet and thereby of the
armature in relation to the stator. It is preferred that the sensor
device comprises a sensor coil that in particular is wound around
the second stator yoke. It is possible in a simple and reliable
manner by means of a simple construction of this type to ascertain
the magnetic flux that is flowing through the second stator
yoke.
Furthermore, it is preferably provided that a control unit is
provided that energizes the coil in dependence upon the ascertained
second magnetic flux. The control unit consequently evaluates the
measured data relating to the magnetic flux, said data being
ascertained by the sensor device, in order by way of example to
determine the position of the permanent magnet and of the armature
in relation to the stator. The control unit energizes the coil of
the first stator yoke in dependence upon the ascertained position
or the ascertained measured data in order to operate the linear
machine. Since the position of the armature and in particular the
permanent magnet in relation to the stator poles is now known, it
is then possible to operate the electrical machine in a reliable
and efficient manner by means of energizing the merely one
coil.
It is preferred that a second coil is allocated to the first stator
yoke, wherein the first coil and the second coil of the first
stator yoke are separated from one another by means of a steel
lamellae package ring, and wherein the permanent magnet of the
armature is arranged in the region of the steel lamellae package
ring in the resting position of said magnet. It is possible by
means of providing a second coil that can be energized to increase
by way of example the power that is produced by means of the linear
machine and where appropriate to increase the frequency of the
oscillating armature.
BRIEF DESCRIPTION OF THE DRAWINGS
The disclosure is to be further explained hereinunder with
reference to the drawings. In the drawings:
FIG. 1 illustrates a first exemplary embodiment of an electrical
linear machine,
FIG. 2 illustrates a plan view of the linear machine,
FIGS. 3A and B illustrate sectional views of the linear
machine,
FIGS. 4A and B illustrate a first magnetic flux and a second
magnetic flux of the linear machine and
FIG. 5 illustrates a second embodiment of the electrical linear
machine, in each case in a schematic view.
DETAILED DESCRIPTION
FIG. 1 illustrates schematically an electrical linear machine 1
that comprises a stator 2 that is fixed to the housing, and also an
armature 3 that can be relocated in a linear or axial manner. The
stator 2 is fixedly arranged for this purpose in a housing that is
not further illustrated in this figure. The armature 3 comprises an
armature shaft 4 that is held in the housing of the linear machine
1 by means of two linear bearing arrangements 5 (only illustrated
schematically in this figure).
Furthermore, a permanent magnet 5 is arranged on the armature shaft
4 and connected in a fixed manner to the armature shaft 4. The
permanent magnet comprises a magnetic north pole N and a magnetic
south pole S. The magnetic axis is aligned through south pole and
north pole perpendicular to the axis of displacement or the
armature axis 7 of the armature 3. Moreover, a resilient element 8
in this case in the form of a coil spring, is arranged between the
permanent magnet 6 and one of the linear bearing arrangements 5,
said resilient element influencing the armature 3 with a resilient
pre-stressing force that counteracts in particular a magnetic force
that is further described hereinunder.
FIG. 2 illustrates a plan view of the linear machine 1. The stator
2 comprises a first stator yoke 9 and also a second stator yoke 10.
The two stator yokes 9, 10 are embodied as open stator rings in an
essentially annular manner and comprise a slot or air gap so that
said stator yokes form an open ring with two free ends that face
one another. Each stator yoke 9, 10 forms on each of its free ends
a stator pole 11, 12 or 13, 14. The stator poles 11 to 14 are
arranged distributed uniformly around the periphery of the armature
3 so that in each case two stator poles 11, 12 or 13, 14 of the
respective stator yoke 9, 10 lie opposite one another. The
permanent magnet 6 is arranged in the air gap between the stator
poles 11 to 14, wherein the magnetic south pole S is allocated to
the stator pole 14 and the north pole N is allocated to the stator
pole 13 so that the magnetic axis of the permanent magnet 6 leads
from the stator pole 14 to the stator pole 13 of the stator yoke
10. If the permanent magnet 6 consequently is in the described
position, said permanent magnet generates a magnetic flux through
the second stator yoke.
Furthermore, a sensor device 15 is allocated to the stator yoke 10,
said sensor device comprising a sensor coil 16 that is wound around
the stator yoke 10 in order to ascertain a magnetic flux through
the stator yoke 10. The magnetic flux through the stator yoke 10
that is generated by means of the permanent magnet 6 can
consequently be sensed or ascertained by means of the sensor device
15. A coil 17 that can be energized is allocated to the first
stator yoke 9 and said coil is wound around the stator yoke 9. A
current flow in the direction of an arrow 18 is generated around
the stator yoke 9 by means of energizing the coil 17, wherein a
magnetic flux is generated by means of the current flow that is
generated in the stator yoke 9, said magnetic flux leading from the
stator pole 11 to the stator pole 12 as indicated by means of the
arrow.
In each case a steel lamellae package 19 is arranged on the side of
the magnetic north pole N and the magnetic south pole S on the
permanent magnet 6. The steel lamellae of the respective steel
lamellae package 19 extend perpendicular to the magnetic flux that
is generated by means of the permanent magnet 6 so that said steel
lamellae guide the magnetic flux of the stator yoke 9 from the
stator pole 11 to the stator pole 12 past the permanent magnet 6,
said flux being generated by means of the coil 17 that can be
energized.
FIGS. 3A and 3B illustrate particular, simplified sectional views
of the linear machine 1, wherein FIG. 3A illustrates a section
through the plane of the stator yoke 9 and FIG. 3B illustrates a
section through the plane of the stator yoke 10. It is evident in
FIGS. 3A and 3B that the stator 2 of the linear machine 1 comprises
a central section having a reduced spacing. This spacing is formed
by virtue of the fact that on one hand the permanent magnet 6 is
provided on its inner side with a lamellae package 20 and that the
stator yokes 9, 10 are provided with a projection 21 on the side
that lies opposite the permanent magnet 6, said projection
protruding inwards, as a result of which the spacing of the annular
stator yoke 9, 10 with respect to the permanent magnet 6 is
reduced. The steel lamellae package 20 is embodied in such a manner
that its steel lamellae extend transverse or perpendicular with
respect to the magnetic axis of the permanent magnet 6 and in this
respect are aligned parallel to the steel lamellae of the steel
lamellae packages 19.
FIGS. 4A and 4B illustrate simulated magnetic fluxes through the
stator yokes 9, 10 (in the so-called d and q axis). The magnetic
flux that is generated by the permanent magnet 6 in accordance with
FIG. 4B extends from the magnetic north pole N, through a first
steel lamellae package 19, an air gap and into the stator yoke 10,
and from there through a second air gap into the second lamellae
package 19 and back into the magnetic south pole S, as a result of
which a closed magnetic circuit is formed. The steel lamellae
package 20 prevents a short circuit of the magnetic flux. The
magnetic conductivity .mu..sub.R occurs in particular in dependence
upon the number and thickness of the steel lamellae. A magnetic
force is generated on the permanent magnet 6 in the direction of
the armature axis 7, as a result of the relocation, to achieve a
minimal magnetic resistance in the air gap. As a consequence, the
permanent magnet 6 having the armature 3 is relocated axially along
the armature axis 7 perpendicular to the magnetic flux that is
excited by means of the permanent magnet 6 or is moved into a
resting position in which the magnetic flux comprises the lowest
resistance. The magnetic flux through the stator yoke 10 changes in
dependence upon the position of the permanent magnet 6 with respect
to the stator poles 13, 14. This is ascertained by means of the
sensor device 15. It is possible to determine a change in the
position of the permanent magnet 6 and thereby the armature 3 in
dependence upon the magnetic flux that is changing. Consequently,
it is possible to precisely determine the position of the armature
3 by means of the sensor device 15 having the sensor coil 17. It is
preferred that the sensor coil 16 is not energized for this
purpose. As a consequence, the position or orientation of the
armature is ascertained independently of a current supply.
Since the magnetic axis of the permanent magnet 6 generates a
magnetic flux only the stator yoke 10, its magnetic permeability
.mu..sub.R perpendicular to the magnetic axis is approximately
1.05, which corresponds approximately to the magnetic conductivity
(permeability) of air. The steel lamellae packages 19 have a degree
of permeability according to the selected steel.
The coil 17 that can be energized is embodied in such a manner that
the magnetic flux that is generated by means of said coil generates
a force in the direction of the armature axis 7, said force being
counteracted by the force is generated by means of the permanent
magnet 6 and is described above. The magnetic force is a
longitudinally-acting force, as illustrated in FIG. 4A, while the
magnetic force through the permanent magnet 6 is a transversal
force, as is illustrated in FIG. 4B.
When operating the linear machine 1 by means of a control unit E
that evaluates the measured values of the sensor device 15 and
accordingly energizes the coil 17, the armature 6 is consequently
moved by means of the permanent magnet in a first direction out of
the stator 2 and is moved into the stator by means of energizing
the coil 17, wherein it is possible by means of the sensor device
15 to determine the prevailing position of the armature 3 in a
simple manner, and thereby it is possible to control or energize
the coil 17 in a precise manner for an oscillating operation of the
linear machine 1. The linear machine 1 is embodied in such a manner
that a magnetically neutral resting position of the permanent
magnet 6, said resting position being caused by means of the
permanent magnet, differs from a magnetically neutral resting
position of the permanent magnet 6, said resting position occurring
by means of energizing the coil 17. If the coil 17 is not
energized, the permanent magnet 6 thus moves the armature 3 into
its first neutral resting position. The permanent magnet 6 is then
moved by means of energizing the coil 17 in the direction of the
resting position that is caused by means of the energized coil 17.
As a consequence, the armature is always relocated into the correct
or the desired position if the coil 17 is energized. The coil 17 is
embodied by way of example as a copper winding, by way of example
having sixty windings.
If the armature 3 begins to oscillate, this occurs in the direction
of the stator 2 or in the direction of the projection 21. If the
armature 3 owing to its acceleration exceeds the neutral resting
position of the armature 3, which is caused by means of the coil
that can be energized, the force ratios thus change in such a
manner that the armature 3 is braked and is accelerated in the
opposing direction. This effect aids braking the armature 3 prior
to said armature reaching the projection 21 so that a mechanical
jam or mechanical contact of the armature and stator 2 is
prevented. The resilient element 9 supports the oscillating
movement.
FIG. 5 illustrates a second exemplary embodiment of the linear
machine 1, wherein elements that are already known from the
preceding figures are provided with identical reference numerals so
that in this respect reference is made to the above description.
Hereinunder, reference is only to be made to the differences.
The exemplary embodiment of the linear machine 1 in FIG. 5 differs
from the preceding exemplary embodiment by virtue of the fact that
the stator 2 comprises a second coil 23 in addition to the coil 17,
said second coil being allocated to the first stator yoke 9. FIG. 5
illustrates in this respect a longitudinal section of the linear
machine 1 through the plane of the stator yoke 9, as is also the
case in FIGS. 3A and 4A. The two coils 17, 23 are separated from
one another by means of a steel lamellae package ring 24 in the
direction of the armature axis 7. The steel lamellae package ring
24 forms the stator poles 11, 12 of the stator yoke 9, said stator
poles being allocated to the permanent magnet 6. The operation of
the linear machine 1 in accordance with the second exemplary
embodiment corresponds essentially to that of the first exemplary
embodiment, wherein the two coils 17 and 23 can be energized
independently of one another in order to control the oscillating
movement of the armature 3.
Fundamentally, the permanent magnet 6 is preferably a rare earth
magnet, in particular NdFe35. In accordance with the second
exemplary embodiment, the resilient element 8 is omitted. The
resilient element 8 could also be omitted from the first exemplary
embodiment. Likewise, the oscillating movement of the linear
machine 1 can be supported in the second exemplary embodiment by
means of providing the resilient element 8. In each case, a hybrid
linear reluctance motor or a hybrid linear reluctance machine is
formed and said reluctance motor or reluctance machine is operated
on the one hand by means of an electrically excited magnetic flux
and on the other hand by means of a magnetic flux that is excited
by a permanent magnet.
* * * * *